Daily Archives: 14/01/2020

As we continue to watch the bush fire crisis in Australia and marvel at the work being done to save the various animals, it is important we check on our own preparedness in New Zealand for bush fires. As climate change takes hold some provinces are going to get drier and become more prone to them, and the Australian bush fires have mos probably shown that if anything, we are not ready.

Whilst arson has contributed some fires to the tally of active events around Australia, they do not account for the biggest or the most damaging. They would not have necessarily gotten established without the help prolonged drought conditions that have afflicted much of the east or the prolonged high temperatures – Australia has been increasingly afflicted by heatwaves that have pushed temperatures frequently into the mid-high 40 degree celsius range.

Once established, bush fires can take on a life of their own. They can create their own weather, which some of the current ones are doing. Pyrocumulus is cumulus cloud created by up drafts from the fires dragging particulate high enough that water vapour starts condensing around it. Pyrocumulonimbus are cumulonimbus clouds that are created by the same phenomena, and like any cumulonimbus they can create lightning. This is happening right now. The pyronado is a tornadic feature spawned by a localised rapidly rotating up drafts caused by the fires. Short lived and unpredictable they can move rapidly.

Bush fires do not affect just their immediate area. Fanned by strong winds the real front is actually not the fire/s, but an area several hundred metres in front in of them where burning embers are landing. If you are in that area, it is time to leave, and leave quickly. If you have another plan, that is the time it needs to be actioned.

A number of other man made factors have hindered the Australian response to their bush fire emergency. They include but are not limited to:

Specialist planes that can pick up water and dump it on fires were considered by the Australian government and then the idea was scratched

The Rural Fire Service went through a period of having an alleged bad culture among its members and management that caused significant numbers of firefighters to walk away

Some brigades are using heavily out dated equipment, including trucks that are not up to the modern requirements of firefighting

Federal Government has been slow to acknowledge the need for monetary compensation for firefighters who gave up their regular jobs to help with the fire fighting

The bush fires in Australia invariably raise questions about protecting New Zealanders from scrub fires, which are a regular occurrence during summer. In provinces like Canterbury, Otago, Hawkes Bay and Marlborough these can start and spread rapidly. In inland areas sometimes only helicopter access is available to those fighting the fires. Whilst we probably do not need water bombing aircraft, helicopters with the capacity to do that would be useful.

City, District and Regional Councils may or may not have factored bush fires into their hazard planning strategies. If not these will now need to be revisited under comparative urgency, lest they experience the problems Christchurch has had following its 2017 Port Hills fire, where a sudden change in wind direction and flammable material meant that fire fighters lost control of a fire they thought was contained. 11 houses were lost.

This also raises questions about the types of vegetation we should be planting. Clearly around urban areas and in hilly terrain where firefighting might be difficult, eucalyptus and other highly flammable vegetation potentially becomes dangerous.